Do the Number and Volume of Surgical Lung Biopsies Influence the Diagnostic Yield in Interstitial Lung Disease? A Propensity Score Analysis

Abstract

IntroductionOur objective was to evaluate whether the number and volume of surgical lung biopsies (SLBs) influence the diagnosis of diffuse interstitial lung disease (ILD). MethodsRetrospective study of SLB for suspected ILD in patients from the Mayo Clinic from January 2002 to January 2010. Data were collected in the institution and analyzed. Results311 patients were studied. Mean number of biopsies was 2.05 (SD 0.6); 1 biopsy in 50 (16%), 2 in 198 (63.7%), 3 in 59 (19%) and 4 in 4 (1.3%). Histopathologic diagnosis was: definitive (specific): 232 (74.6%), descriptive (non-specific): 76 (24.4%), no diagnosis: 3 (1%). After excluding patients without diagnosis (n=3), there were 50 patients with only 1 biopsy, 196 with 2 and 62 with 3 or 4; the definitive diagnostic yield was similar in all 3 groups (37/50; 74%, 150/196; 77%, and 45/62; 73%) (Chi-square, P value .8). The propensity score analysis between patients with 1 SLB and patients with more than 1 SLB also showed no difference in diagnostic yield. Regarding the volume of biopsies, mean total volume was 34.4cm3 (SD 46): 41.2cm3 (3 cases) in patients with no diagnosis; 33.6cm3 (232 cases, SD 47) in patients with specific diagnosis; and 36.6cm3 (76 cases, SD 44) in patients with descriptive diagnosis. Biopsy volume had no influence on histopathology yield (ANOVA, P value .8). ConclusionsThe number and volume of the biopsy specimens in SLB did not seem to influence diagnosis. Based on our results, we believe a single sample from a representative area may be sufficient for diagnosis. Randomized prospective trials should be performed to optimize SLB for ILD.